With about 75 onlookers waving goodbye from the Inner Harbor dock, a Soviet training ship sailed for Europe today minus two naval cadets who jumped ship yesterday and apparently sought asylum at the downtown office of the U.S. Immigration and Naturalization Service.

The two cadets were identified by crew members as Alexei Litovko and Pyotr Zolotorev, both from Kaliningrad and about 20 years old.

The Sun reported today that the two left the tall ship

Kruzenshtern yesterday afternoon and ran straight to the nearby INS office in Hopkins Plaza, about four blocks away.

A spokesman for the INS in Washington, D.C. said today that all asylum cases are "confidential because the applicant fears persecution from his government." The spokesman, Vern Jervis, would not comment on the two cadets.

Yesterday's incident was the second case within a week of a Soviet seeking asylum in the U.S. According to a U.S. State Department spokeswoman, an unidentified Soviet seaman jumped ship in Jacksonville, Fla. "late last week" and requested asylum from federal officials there.

"As in all of these cases, this is in the purview of INS," the spokeswoman said today.

The INS district director in Baltimore, Walter D. Cadman, refused to confirm or deny that the two cadets had requested asylum. He did not answer calls to his office today.

But he told The Sun yesterday that "We know of the whereabouts of the two gentlemen, and we would simply say that they're safe and they're well." He indicated the cadets had not returned to the ship.

An FBI spokesman in the Baltimore office said today the agency would normally have a minimal interest in the two Soviets "if they have any effect on foreign counter-intelligence." Dave Williams, the spokesman, said the FBI has made "no determination" in the Baltimore case.

Official comment from the Soviet embassy was not available today.

The Kruzenshtern, a four-masted vessel with 160 cadets, 20 officers, eight teachers and 45 crew members aboard, has been docked in Baltimore for 10 days. Tourists had been allowed on board for escorted tours, and uniformed Soviet naval cadets have become a familiar sight at the Inner Harbor.

William M. Runnebaum Jr., a private banker in Baltimore who resides in Federal Hill, arrived at the ship about 6 p.m. to remind five cadets he befriended of a cookout at his home later last night. He said he had entertained some of the cadets "five or six other times. We had a great time."

Runnebaum said one of the cadets told him over the ship's railing that the crew was not allowed to leave. When he asked to go aboard, Runnebaum said, he was taken to the captain-on-duty, who explained that no one from the crew would be allowed to leave.

A crew member later told Runnebaum two cadets had jumped ship after they had been told that no crew members would be allowed to leave the Kruzenshtern on its last day in Baltimore.

"It came as quite a surprise to me," Runnebaum said.

"They all obviously like the U.S.," he said. "They've been limited to what they can do because of the convertibility of their money. But most expressed that they wanted to stay in the Soviet Union. They all have family."

Today, Runnebaum said, "They liked what they saw here in the past week. But there was an unwillingness to defect. There were, as I said, some who have families at home. There was another sailor who had been married only six months ago and wanted to go back home to his wife."

Last night, the remaining cadets lined the deck of the ship and talked over the side to those on the pier.

Asked what the two missing cadets were like, the cadets said, "They were completely normal guys. They were good students."

When asked why the two would chose to defect now, one of them replied: "They were already here."